Many sporting activities today require repeatedly performing actions in a predetermined manner, which require different movements of a player's left and right feet. For example, in golf, the golfer's footwork during the swing is complex and differs between left and right feet. In general, for most golf shots the golfer's weight is initially loaded 50/50 on each foot and the golfer's weight is typically distributed evenly across the bottom surface area of each foot. During the backswing, a majority of the golfer's weight typically shifts to the outside (lateral side) of the golfer's back foot while the front foot maintains some weight for balance. The backswing applies forces tending to spin or pivot the back forefoot outwardly and the back heel inwardly, which must be resisted by the back foot's contact with the ground to keep the golfer's back foot stable.
During the downswing of the club, the golfer's weight begins to shift and by the time the golf ball is struck, the golfer's weight is again evenly distributed between the rear and front feet, or has started to shift more to the front foot. At the finish position of the swing, most of the golfer's weight is on the front foot with more weight on the outside (lateral side) of the front foot than the inside (medial side), and the golfer's heel and shoe outsole of the back foot are elevated above the ground and face rearwardly. In a proper swing, only the toe portion of the golfer's rear foot remains in contact with the ground at the finish. In the finish position, the heel and most of the outsole of the golfer's rear shoe are off of the ground, with only the toe portion contacting the ground for balance.
As discussed above, the golfer's feet make complex movements during a golf swing to keep the golfer balanced while generating torque and club head speed to strike the golf ball. During various stages of the golf swing, different forces, pressures and stresses are exerted on the left and right shoes, which require each shoe to perform and react in different ways. Similar circumstances exist during other sports such as baseball (e.g., during a batter's swing) and track & field (e.g., during start and running in a counter-clockwise direction on a track). Conventional shoes used during these types of sporting activities, however, are generally symmetrically designed and do not distinguish between different left and right foot actions and movements that may require different functionality, features and structures in the left and right shoes to optimize their performance during the sporting activity.
Additionally, in conventional golf shoes, the outsole includes a rigid base platform that supports various traction elements in way that provides very little independent movements between the traction elements. Typically, the outsole moves as a rigid unit such that when the heel lifts or the foot tilts to the side, a majority of the sole lifts off the ground and loses traction, leaving only the toe or a side edge in contact with the ground for traction. Furthermore, in conventional golf shoes, the sole lacks cushioning or flexibility to promote smooth energy transfer between the ground and the golfer's feet during the golf swing. The relatively rigid soles of conventional golf shoes can also be uncomfortable to a golfer compared to other types of athletic shoes.